EAST HAMPTON, New York, May 21- Judging by early demand for everything from doggie daycare to Ferrari rentals and fine art, rich Americans are going to make this a strong summer in one of their favorite playgrounds- the beach towns on the eastern end of Long Island collectively known as the Hamptons.

Stocks closed sharply lower across the board Wednesday, with all key S&P sectors in the red, following a batch of weaker-than-expected earnings and as commodities resumed their selloff amid ongoing worries over global growth.